Sensing devices for use in rapid thermal response sensors including pyroelectric thick and thin layers have been subject to the influence of the substrate material on which they were deposited. Their ability to respond to thermal changes has depended on the thermal conductivity of the substrate. If the substrate were free standing, the heat loss to the surrounding ambient would be at a minimum and the optical response would be greatly increased. Films that have been attached to substrates have also been restricted in their ability to respond to mechanical deformation. In this sense, a free standing film would act as a deformable membrane and could be used for sensor applications. A free standing film that is to be used as an infrared sensor would not need any cooling to remove heat that accumulates upon absorption of radiation.
Substrate free or free standing films of pyroelectric materials have been made heretofore for use as infrared sensors. These films, however, were grown on glass substrates and as a result were polycrystalline.